12AX7 / ECC83 NOS RAYTHEON Long Black Plates Tested Tube - Balanced - Made in USA '61

12AX7 / ECC83 NOS RAYTHEON Long Black Plates Halo Getter Tested Tube Made in USA '61 AMPLITREX Tested – VERY STRONG – Low Noise & Microphonics – Balanced – Vintage American RAYTHEON Production Description: This 12AX7 / ECC83 Raytheon NOS, produced in the United States in 1961, represents one of the most appreciated American productions from the golden age of signal tubes. The construction with Long Black Plates and Halo Getter identifies a classic Raytheon configuration from the early 1960s, highly sought after by enthusiasts for its build quality, reliability, and distinctive sonic character. Raytheon was one of the most important companies in American electronics history, and its ECC83 long black plates are still considered among the most interesting vintage USA productions for quality audio applications. This specimen has been carefully verified using an AMPLITREX AT-1000 Tube Tester, resulting VERY STRONG, with electrical performance very close to the nominal reference values and excellent balance between sections. The Low Noise & Microphonics selection makes it particularly suitable for sensitive circuit positions, including input stages, phono stages, and V1. Sonic Characteristics Raytheon Long Black Plates are appreciated for a rich, fluid, and musical sonic presentation, with a typically American personality characterized by body, naturalness, and excellent intelligibility. Bass The bass range is full and well-structured, with good presence and a pleasant sense of solidity that supports the reproduction without weighing it down. Mids The mids represent one of the strengths of this production. Vocals are textured, credible, and engaging, while acoustic instruments and harmonics maintain a rich and natural texture. Highs The highs are open, refined, and well integrated into the musical message. Detail is present without being aggressive or artificial. Dynamics Dynamic response is fluid and well-controlled, with excellent ability to follow variations in intensity and musical nuances. Soundstage The soundstage appears wide and stable, with good instrument focus and an orderly presentation of the acoustic space. 🎧 Use in Hi-Fi Amplifiers This Raytheon ECC83 is particularly suitable for: tube preamplifiers line stages phono stages integrated amplifiers compatible driver stages restoration of vintage American hi-fi electronics The Low Noise & Microphonics selection makes it particularly interesting even in the most sensitive positions of the circuit. 🎸 Use in Musical Applications In the musical instrument amplifier sector, Raytheon Long Black Plates are appreciated for: natural harmonic response rich and well-present mids good dynamics contained noise balanced musicality Characteristics that make them interesting for both vintage amplifiers and modern boutique designs. 🎯 Note for audiophiles and technicians Authentic Raytheon Long Black Plates Made in USA represent one of the most fascinating productions of the American ECC83 tradition. The combination of: original USA Raytheon production 1961 year Long Black Plates Halo Getter Low Noise & Microphonics perfectly balanced sections VERY STRONG performance makes this specimen particularly interesting for those looking for a quality vintage American ECC83, capable of combining reliability, musicality, and historical charm. A selected tube that expresses the authentic character of the best Raytheon production of the early 60s, in true Vacuum Tubes Treasures style. Test Results Tested on AMPLITREX AT-1000 Tube Tester Voltage Test: Va = 250V, Vg = -2V Average 100%: Gm = 1600 ; Ia = 1.2 mA TEST RESULT: VERY STRONG Tube : Section 1: Gm = 1600 ; Ia = 1.1 mA Section 2: Gm = 1600 ; Ia = 1.1 mA Additional Tests Performed: Microphonics: Low. Tested and suitable for hi-fi use, including phono stages and guitar amplifiers. Also suitable for V1. Balance: Very good. The sections are consistent and well-aligned, making the tube also suitable for use as a phase inverter in hi-fi and instrumental applications. Emission Quality: Excellent – Very strong and stable emission, without fluctuations. Short Circuits and GAS: Absent. Conditions: Condition: NOS - New Old Stock - Tested and working - Supplied in our custom box for optimal protection. Functionality: Perfectly operational. Aesthetic Condition: Very Good – Legible lettering with slight signs of age, no obvious defects. See photos for details. Manufacturing Code: 280 61-21 → 280 → Raytheon Manufacturing Company, Waltham 54, Mass. ; 61-21 → RMA/EIA Open Date Code → manufactured in the 21st week of 1961 Discover why our tubes are different →